As an in-phase corporate-feed circuit that generates plural signals having equal phases from a single signal, an in-phase corporate-feed circuit having a circuit configuration of tournament type is disclosed in Patent Literature 1 listed below.
In this in-phase corporate-feed circuit, plural power dividers of Wilkinson type each of which is provided as a power divider that divides a single signal into two signals in phase are formed in a plane circuit.
Further, transmission lines that connect the plural power dividers in the shape of a binary tree are formed in the plane circuit.
An in-phase corporate-feed circuit can be used for an array antenna apparatus which is typified by a phased array antenna.
A phased array antenna is one in which plural element antennas are arranged, and can vary the transmission directions of electromagnetic waves which are transmission waves by changing the phases of signals to be outputted to the element antennas.
Typically, a transmitter is connected to each of the element antennas, and is equipped with a phase shifter that can vary the phase of a signal.
Therefore, in order to control the phase of an electromagnetic wave emitted from each of the element antennas, it is necessary to input a signal to the transmitter equipped with the phase shifter.
Because there are many cases in which the phase shifters mounted in the plural transmitters can control the phases of signals more easily when the phases of the signals inputted to the plural transmitters are equal, there is a case in which the in-phase corporate-feed circuit is configured to generate plural signals having equal phases from a single signal, and provide the signals in phase for the plural transmitters.